There has been a recognition that the United States is at risk of the delivery of weapons of mass destruction to its ports by enemies employing a strategy of hiding such a weapon in a shipping container. Various schemes have been proposed for x-raying containers or otherwise examining containers as they are loaded on ships in foreign ports. Such schemes, however, can be very limited in effectiveness since they can be defeated with x-ray shielding, vulnerable to compromise by rogue employees and the contents of the containers altered after they are loaded in a foreign port.
Approximately sixteen million twenty foot containers are in use throughout the world. Additionally, approximately 40% of the personnel that load and off-load these containers come from nations that are on the terrorist list. Bribery and sabotage are common throughout the shipping industry, including government officials, shipping companies and freight forwarders. Large quantities of contraband material now pass through the maritime commerce into most ports in the U.S.
The current shipping containers are primarily made of steel with considerable drawbacks. The steel containers increase shipping weights unnecessarily, wear out quickly, and can be infiltrated by simple means. Other panels not made of steel have been considered, but they are typically not made of weldable material (i.e. material which is suitable for undergoing welding without experiencing a substantial amount of damage). Weldable material such as steel is provided to form a right angel joint between a vertical corrugated frame and a horizontal beam, such as a side panel joining to the upper and lower container frames. By way of contrast, a composite panel can form a very strong glue bond with a metal flange that is in the same plane where the gluing can be accomplished with pressure.
To a limited degree, the notion of enclosing detecting devices, such as sensors or processors, in containers, which communicate with external systems, has been implemented in unsecure applications. For example, Sensitech, based in Beverly, Mass. (www.sensitech.com), provides solutions in the food and pharmaceuticals fields that are used for monitoring temperature and humidity for goods, in-transit, in-storage, and display. Such, temperature and humidity monitors are typically placed in storage and transit containers to monitor if desired conditions are maintained.
However, such data collection is not generally considered sensitive with respect to security issues. Rather, it is used for ensuring that products in a container do not spoil by being subjected to unfavorable temperature and humidity conditions. Secure communications, tamper resistance, and detection are not particularly relevant issues in such settings. Additionally, such monitors do not monitor for the presence of suspicious content or materials, no matter where they may be introduced in the chain.
Even if detectors are introduced into a container and interfaced to an external system, an “enemy” may employ any of a variety of strategies to defeat such a detection system. For instance, an enemy may attempt to shield the suspicious materials or activities from the detectors; defeat the communication interface between the detectors and the external system, so that the interface does not report evidence of suspicious materials or activities sensed by the detectors; disconnect the detectors from the interface; surreptitiously load a container that contains an atomic weapon, but that does not contain detecting devices, onto a container ship; overcome external systems so that they incorrectly report on the status of the detectors.